Final answer:
The relationship between absorbance of light by a solution and its concentration is linear as per Beer's law.
Step-by-step explanation:
The relationship between the absorbance of light by a solution and its concentration is typically described by Beer's law, which states that there is a linear relationship between absorbance and concentration. This can be expressed mathematically as A = εcl, where A is the absorbance, ε is the molar absorptivity or extinction coefficient, c is the concentration of the solution, and l is the path length through which the light passes. It is important to note that this linear relationship holds true as long as the system follows Beer's law, which is generally applicable within a certain range of concentrations and under conditions where the absorbance is directly proportional to concentration.